Support pasting from clipboard

[yusanshi]

Add support for getting image from clipboard (For example, use Windows+Shift+S to capture a screenshot then Ctrl+V in the website).
Test OK on Chrome 78. Not working on Microsoft Edge.

[ZARk-be]

please disable your auto-code-format function. I was curious to see the code needed to do that, but there's so much diff because you add spaces before brackets etc...

[yusanshi]

Well it's my fault ... 😅😅
Fixed now.

[Schaidhauer]

A tip if you want to preview the image after the 'paste' event:

onNewFile: function(id, file)
{
if ((file.type == 'image/png') || (file.type == 'image/jpg') || (file.type == 'image/jpge'))
{
$('').attr('src', window.URL.createObjectURL(file)).width('100px').height('100px').appendTo($('#drag-and-drop-zone'));
}}